A CO 3-2 line (345 GHz, 870u) raster map made with RxB3 of the interface between the expanding W28 supernova remnant and its ambient molecular cloud. The arc of emission reflects the roughly circular shape of the remnant. The CO gas is heated and accelerated by the shock produced as the remnant collides with the quiescent cloud. The angular resolution is 13 arc-sec and the map took about 45 minutes to make. (Courtesy D. Frail and G. Mitchell)

A raster map of the comet Hale Bopp taken on March 16, 1998 in the HCN 4-3 line at 354 GHz (870u). At this time the comet was about 2 weeks prior to perihelion passage and at a distance of about 1 A.U. from the Sun. The coma, as seen here in HCN, spans 125,000 km. The angular resolution is 13 arc-sec. and the map took about 1.5 hours. (Courtesy D. Jewitt, H. E. Matthews and M.Senay)